Thermal Noise Source - white noise sample file

[kingleoric]

Hello!

I just used a sample multisim file and there is a problem I cannot solve and I neither found  a solution here.

I use Multisim 12 for school and I am experimenting with the multisim sample file WhiteNoise.ms12

from the directory

National Instruments\Circuit Design Suite 12.0\samples\Educational Sample Circuits\Miscellaneous

(you can open it by menu File/Open Samples)

Now here is what i did, I opened the file and replaced XSA2 (a spectrum analyser) for an oszilloscope

to watch the voltage at the resistor R2. Now I start the simulation and double click on the oszilloscope

and I can see the signal and the white noise. well, so far so good. now I stop the simulation and

double click on the Thermal Noise Source to edit some properties or in fact you do not have to change

anything, just close the window with OK (not cancle!) and now simulate again: the noise is gone!

Can anyone help me with this problem? I can't get back the white noise.

(I worked with a copy of the sample file, so I did not destroy anything.)

Thank you very much for your help!

Mathias

[Tien_P]

Hi Mathias,

I see the problem and this is strange. After you open the white noise properties dialog then close it, when looking at the model in the background the noise settings are empty, that’s why you see a square signal source. In the attached circuit, I replaced the noise source with one from the current database and it does have the same problem.

[kingleoric]

Hello Tien!

Thank you very much for your help! I copied your noise source into my project and it works fine! I now can edit the properties of the noise source and the noise does not disappear! 🙂

Best regards,

Mathias